PROJECT SUMMARY Children insured through Medicaid, in comparison to privately-insured children, suffer from higher rates and more severe oral health problems, but are less likely to use dental services. Florida has one of the lowest percentages of dental use among Medicaid children, given the number of dental practitioners who accept Medicaid coverage. To address this problem, previous research has examined system-level factors that influence access to dental care, such as reimbursement rates and dental practitioner density. However, limited research has examined patient- and practitioner-level mechanisms that contribute to lower use of dental service use in this population (e.g., the relationship between the patient and the practitioner affect use of health services based on the health-care practitioners? beliefs and attitudes, interpersonal communication style, acceptance of different types of insurance). To test a multilevel model of healthcare use, this study will use a mixed-methods research design to characterize the perceptions of both dental care practitioners and low- income caregivers of children with Medicaid dental coverage in Florida. This research design and focus on both patient- and practitioner-level factors will provide a more granular investigation of core determinants of dental service use among an underserved population from two important perspectives. I will evaluate constructs related to perceptions, attitudes, and cognitive beliefs of low-income caregivers and dental practitioners in Florida through sequential qualitative and quantitative data analyses, including perceived lack of access to dental practitioner who accepts new Medicaid patients, attitudes toward the dental care practitioner or low-income caregiver, and beliefs about the importance of the patient-practitioner relationship. I predict that both groups will identify converging and diverging determinants of low dental service use among children with Medicaid coverage. Results will lay the foundation for research on barriers and facilitators identified in a nationally representative sample and ultimately the development of a multi-perspective intervention targeting practitioner-level factors.